VERITAS - AEQUITAS

Any brake system using common glycol-based brake fluid (e.g., DOT3) should be completely flushed at least every 2 or 3 years. The brake fluid can pick up water from the atmosphere and eventually this leads to corrosion in the cylinders and sticky calipers. Unfortunately, very few people ever bother to do this preventative maintenance.

A small amount of contact between the brake pads and the disk is normal. The high points on the rotors kick the pads back from the discs to minimize drag.

As an aside, this small drag has been looked at by automotive manufacturers because it decreases mpg efficiency. Braking systems have been developed to pull the pads back from the rotors so there is no drag from the pads when retracted. There is an unanticipated problem with this: In a conventional system, the pads and rotors are kept warm while the vehicle is driving, but not so when the pads are purposely retracted. In below-freezing temperatures, water splashed onto the rotors can freeze, ruining braking ability, and this is why you don't see such systems on consumer vehicles.